Safety valve for gas burners



Feb. 25, 1930. A. KAL@ 1,748,554

- SAFETY VALVE FOR GAS BURNERS Filed Sept/21, 1928 a@ 741ML atto: nu;

Patented Feb. 25,1930

UNITED STATES 'PATENT' OFFICE ALBERT KALO, F COLUMBUS, OHIO, ASSIGNOR OF ONE-HALF TO GEORGE GHI?, 0F

CANTON, OHIO SAFETY vVALVE ron ens BUn-.Nuns

Application led September 21, 1928. Serial No. 307,354.

This invention relates to an improved safety valve structure designed for use particularly in connection with gas burners, and has for its primary object the provision of an auxiliary valve construction having thermostatic features of control whereby when the burner is in operation, producing heat,'the auxiliary valve structure will be maintained automati- 'cally in an open position, permitting of gas flow to the 'burner but wherein should the gas flow be momentarily interrupted for any reason and combustion at the burner discontinued the said auxiliary valve structure functions automatically to arrest gas flow or to prevent the uncontrolled escape of gas, without combustion thereof, to the atmosphere.

Ordinarily gas burners are provided with manually operated control valves so constructed that when rotated gas flow from a conduit or main, supplying such fuel, to an associated burner is permitted. It frequently happens through accidental causes and for other reasons that the main manually operated valve assumes an open or partially open position, admitting of gas flow to the burner and theescape of such gas to the atmosphere without combustion. Children frequently open such valves or again the supply of gas in the main or conduit supplyin the burner may `for certain reasons be iscontinued which, as above stated, permits of uncontrolled gas escape unless the condition is .properly controlled by the main valve.

It is the principal object of the present invention to provide an auxiliary emergency valve structure which cooperates with a gas burning system of the character set forth above whereby in the event the heat incident to the combustion of gas at the burner should for any -reason fail the said auxiliary valve mechanism operates automatically to arrest further gas flow to the burner or the escape of such gas to the atmosphere until controlled by manual operations.

It is another object of the invention to provide an auxiliary valve mechanism with a manual feature of control by which such auxiliary valve mechanism may be held manually in an open position when the burner is irstvoperated, the construction of the valve mechanism being such that after combustion has been initiated further manual regulation is rendered unnecessary.

For a further understanding of the invention reference is to be had to the following description and the accompanying drawing, wherein: l l

Figure 1 is a plan view of a gas burner and associated valve mechanism employing the present invention,

Figure 2 is a vertical longitudinally sectional view on the line 2-'2 of Figure 1,

Figure 3'is an enlarged vertical sectional view taken through the manually operated valve and the auxiliary automatic valve,

Figure 4 is a transverse vertical sectional view on the line 4,-4 of Figure 1,

Figure 5 is a transverse sectional view' on the line 5-5 of Figure 3.

Referring more particularly to the drawings the numeral 1 designates a gas burner structure of the type commonly employed in connection with gas burning stoves, ranges and the like. This structure, which comprises a burner head 2, a gas supply pipe 3, a manually operated main valve 4, and a mixing conduit 5, into which gas from the sup' ply pipe 3 is delivered by the opening of the valve 4, in which conduit air from the atmosphere is intimately mixed with the gaseous fuel and delivered in commingled form to the burner head 2 for combustion purposes.

The conduit 5 includes an enlarged mixing chamber 6'at the forward end thereof which includes an apertured front wall 7 which cooperates with a rotatable shutter disk 8, which is also apertured to register with the opening in the wall 7 The amount of air enterin the mixing chamber 6 is governed, as usua by controlling the positions of the disk 8 to enlarge or diminish the effective areas of the apertures in the Walls 7 and 8 through which the air enters the mixing chamber. p

The wall 7 'is provided with a longitudinally and axially v extending pipe section 9, which is formed to include a longitudinally extending bore 10. vThe outer end of this of the casing tion of the inner end of the valve casing 11 of the manual valve 4, while the opposite end 11 is threadedly received Within an opening ormed in the supply pipe 3. The casing 11 is, as usual, provided with a rotatable valve plug 12, formed with an opening 13 which registers with aligning passages 14 provided 1n the casing 11. lVhen these parts are in the position shown in Figure 3, gas may pass from the supply pipe 3, through the manually operated valve 4 and thence into the pipe section 9 for admittance into the mixing chamber 6. The plug 12 is operated by the usual handle 15 and is adapted to be retained in its positions of adjustment by a spring 16, all of which is a customary construction.

The present invention provides a safety attachment for the standard form of burner construction and provides an auxiliary valve mechanism, described in its entirety by the letter B. Preferably, this mechanism comprises a bell crank lever 17, which is pivotally mounted as at 18 within the confines of the chamber 6. The lever includes a forwardly and outwardly protruding arm 19 which extends through the mixing chamber and through registering openings formed in the Wall 7 and the disk 8, the said arm terminating in an exterior finger engaging portion 20, located contiguous to the -handle 15 of the valve 4. It will be seen that by depressing the arm 19, the lever will be rocked about its pivotal axis 18. Such movement .of the lever is normally restrained by means of a coil spring 21 which has one of its ends attached to the lever and its other end hinged to the wall 7.

The shorter arm 22 of the lever 17 has its lower end pivotally connected as at 23 to a needle stem valve- 24, which is positioned normally, as shown in Figure 3, to restrict gas flow through the longitudinal bore 10 of the pipe section 9, thus preventing the flow of gas into the mixing chamber independently of the manual valve 4.

To govern the automatic functioning of the needle valve I provide a thermostatic rod 25 of a material, preferably metal which responds quickly in the matter of expansion and contraction, to the influence of the heat generated by the combustion of gas at the burner head. One end of the thermostatic rod 25 is positioned within a socket 26 formed in the lever 17, while the other end of said rod is rigidly secured by means of a set screw 27 to the inner wall of a tubular passage 28 formed as is customary in the head 2. By this provision of a set screw 27 the operating positions of the rod 26 may be governed or set to function as desired in response to the heat developed around the burner head. Except for the set screw 27 the rod or stem 25 may expand and contract without interference and for this reason it is slidably received for free and unobstructed movement in openings formed in the walls of the passage 28. The stem where it passes through the passage 28, is protected by means of a stationary guard 29, in this instance integrally formed with the head 2, said thermostatic guard being arranged directly over to prevent injury to the latter by the placing of objects upon or near the burner structure.

In view of the foregoing it will be seen that the present invention provides a simple, substantially automatic auxiliary valve structure for use in combination with gas burners whereby uncontrolled escape of gas from such burner is effectively precluded. To operate the burner to admit of gas flow therethrough, it is first necessary to open the valve 4 as usual. Following this the finger portion 20 of the bell crank lever is depressed so that said lever will be oscillated to withdraw the stem 24 from its normal position obstructing gas flow through the bore 10. The opening of the bore 10 allows gas to flow into the mixing conduit 5 where it is intermingled with air and delivered to the burner head in combustible proportions. Combustion may then be started at the burner head by any suitable means so that heat is immediately developed in the vicinity of the burner. This heat then acts upon the rod 25 to effect its expansion. As a matter of fact the operation is substantially instantaneous after combustion has been initiated at the burner head, expansion of the rod 25 then operates to maintain the valve stem 24 in its Aopen position and the finger portion 2O may be released andthe burner structure will then o erate in thel normal manner. The closing o the valve 4 arrests combustion at the head 2,` so that the stem or rod 25 will contract, allowing the spring 21 to move the stem 24 to its normal position of bore closure. If for any reason gas flow should be interrupted to the burner structure, While the latter is in operation and without the normal closing of the valve 4, it will be seen that the auxiliary valve operates nevertheless to arrest gas flow, since if combustion is at any time discontinued the rod 25 contracts so that the stem 24 will be returned to a position of bore closure. The mere opening of the valve 4 will not permit of gas escape unless combustion is initiated at the burner head, and the loperation of both the valve 4 and the lever 17 will only operate to permit of gas escape just so long as both valve and lever are retained in an open position.

lVith these features of construction a safety valve of improved form is provided by which controlled flow of gas to a burner head is greatly facilitated in both an improved and safe manner.

While I have described what I consider to be the preferred form of the invention, neverthe-less I do not limit myself to the exact del tails-of construction illustrated and disclosed but reserve the right to employ all such modifications and variations thereof that may be said to fall within the spirit and the scope of the following claims.

What is clamed is: l l. In a gas burner system, a burner head provided with a gas and air inlet conduit, a gas inlet pipe entering one end of said conduit, a lever positioned within the conduit and pivoted contiguous to said inlet pipe,

said lever being provided with an actuating portion arranged exteriorly of said conduit, a valve member connected to said lever and normally operative to obstruct the gas liow from said pipe into said conduit, spring means normally s'erving -to maintain said valve member in a closed position, a horizontally extending thermostatic element having one end rigidly connected to said burner head and the other end loosely engaging saidlever, said thermostatic element having a' portion thereof situated within the zone of heat -generated by the combustion of gas at said burnerl head, whereby when said burner is in operation said thermostatic element will expand to maintain said valve member in an open position.

2. In a gas burner system, a burner head provided with an air and gas inlet conduit. a gas suppl pipe entering said conduit and formed wit a restricted bore, a valve member for controlling gas ilow through said bore and into said conduit, a lever pivotally mounted within said conduit and having an operative connection with said valve member, means cooperative with the lever and tending to maintain said valve member normally in a position obstructing gas flow through saidl bore, said lever being provided with an exteriorly extending actuating portion by which said lever may be rocked normally to move said valve member to a position opening said bore, and a longitudinally extending thermostatic element arranged to pass through said conduit and to have -one end thereof rigidly connected to said burner head and extending across the central portion of the latter and the other end loosely positioned within a pocket formed within said lever, whereby upon the dperation of said lever to open the valve the thermostatic element willv remain stationary with said burner head, but When expanded due to heat generated by the combustion of gas at said burner head, will move into engagement with said lever to maintain said valve member automatically in an open position. l

3. In a gas burner system, a burner head provided with a gas and air inlet conduit, a gas inlet pipe entering one end of said conduit, a bell crank' lever pivotally mounted within said conduit contiguous tosaid inlet pipe, said lever being provided with an actuating portion arranged exteriorily of said conduit, a valve member connected with the other end of said lever and normally operative to obstruct said gas ilow from said pipe into said conduit, spring means normally serving to maintain said valve member in a 1 closed position, a horizontally extending thermostatic rod cooperative with said lever and said burner head to maintain vsaid valve member in an open position against the iniluence of said spring whencombustion takes place at said burner head, and means admittingof adjustment in the operating positions of said thermostatic element.

4. In a gas burner system, a burner head provided with an air and gas inlet conduit, a gas supply pipe entering one end of said conduit and formed with a restricted bore, a needle valve member for controlling gas flow through said bore and into said conduit, a bell crank lever pivotally mounted within said conduit and having a pivotal connection with said valve member, -a spring cooperative with the bell crank lever and tending to maintain said valve member normally'in a position obstructing gas flow through said bore, said lever being provided with an exteriorly extending actuating portionby which said lever may be rocked manually to move said 'valve member to a position opening said bore, and a longitudinally extending thermostatic element arranged to pass through said conduit and to. terminate adjacent to the central portion of said 'burner head, said thermostatic element being situated within the zone of heat generated by the combustion of gas at said burner head,whereby when said burner is in operation said thermostatic element is` expanded to maintain said valve member automatically in an operating position.

5. In a gas burner system, a burner head providedwith an air and gas inlet conduit, a gas'supply pipe entering one end of said extending thermostatic element arranged to pass through said conduit and to terminate adjacent to the central portion of said burner head, said thermostatic element being situated within the zone of heat generated by the combustion of gas at said burnerl head, whereby when said burner is' in Voperation said thermostatic element is expanded to maintain .said valve nember automatically in an operating position, and a guard carried by said burner head arranged to protect the heat responsive portion of the thermostatic element'l 1n the. center of the burner head.

In testimony whereof I aix my signature,

ALBERT KALO. 

